Bicycle-frame.



A. LEVEDAHL.

BICYCLE FRAME.

APPLICATION FILED DBO. so, 1907. RENEWED DEC. 12, 1908.

Patented Mar. 2, 1909.

A. LBVEDAHL.

BIGYCLE FRAME.

APPLICATION FILED DBO. 80, 1907. RENEWED DEC. 12, 1908.

Patented Mar. 2, 1909.

z. I m J m S Mm 1 ION m m MW i Mm i m .mw mm m8 Wm WM \\\\\\V\\\vV m5 RM UNITED strA'rEs PATENT FFTQ AXEL LEVEDAHL, OF AURORA, ILLINOIS,ASSIGNOR TO AURORA AUTOMATIC MACHINERY COMPANY, OF AURORA, ILLINOIS, ACORPORATION OF ILLINOIS.

BICYCLE-FRAME Specification of Letters Patent.

Patented March 2, 1909.

Application filed December 30, 1907, Serial No. 408,562. RenewedDecember 12, 1908. Serial No. 467,220.

To all whom it may concern:

Be it known that I, AxnL LEVEDAHL, a citizen of the United States, and aresident of Aurora, in the county of Kane and State of Illinois, haveinvented certain new and useful Improvements in Bicycle-Frames; and I dohereby declare that the following is a full, clear, and exactdescription thereof, reference being had to the accompanying drawings,and to the numerals of reference marked thereon, which form a part ofthis specification.

This invention relates to improvements in bicycle and motor-cycle framesand refers more specifically to an improved spring connection betweenthe front fork and the stcering head of the frame so constructed andarranged as to yieldingly transmit the load on the frame to the frontfork and to cushion or absorb shocks or blows transmitted to the framein passing over rough and uneven roadways.

The invention consists in the matters hereinafter set forth and moreparticularly pointed out in the appended claims.

In the drawings :Figure 1 is a fragmentary side elevation of the forwardpart of a bicycle frame, showing my invention applied thereto. Fig. 2 isa central, vertical section thereof. Fig. 3 is a section, taken on line33 of Fig. 1. Fig. 1 is a section, taken on line 44 of Fig. 1. F ig. 5is a fragmentary section, taken on line 5-5 of Fig. 3. Fig. 6 is adetail of an antifriction bearing as seen from the line 6-6 of Fig. 3,looking in the direction indicated by the arrows. Fig. 7 is aperspective view of the upper end of the front fork spindle.

The front fork 10 of the frame comprises two lateral members 11, 11which extend at their lower ends at the sides of the wheel 12 and arefixed rigidly together above the wheel by transverse connections. Saidtrans verse connections consist, as herein shown, of upper and lowertubular bars 15, 16, respectively, each made an integral part of afitting provided with lugs 17 which enter the sheet metal tubular partsof the fork members in the manner shown in Fig. 2.

18 designates the tubular steering head of the frame to which areconnected, in the usual manner, the top and bottom members 19, 20, resectively, of the frame.

21 designates the fork spindle which is rotatively mounted in thesteering head and spindle.

22 designates the handle bar stem which fits within and is clamped tothe upper end of the fork-spindle, the latter being made hollow toreceive said stem. The said forkspindle and the surrounding steeringhead are located in rear of the upper end of the front fork, and thespindle is connected at points above and below the steering head 18 withthe fork through the medium of flexible and yielding connections whichconstitute my invention and which will now be described. The saidfork-spindle is disposed parallel with the upper end of the fork and isloosely connected with the fork by upper and lower pairs of verticallyswinging links 25 and 26, respectively, which are pivotally connected attheir front and rear ends to parts carried by the fork and fork-spindle,respectively. As herein shown, the forward ends of said upper and lowerlinks are pivotally connected with the fork through the medium of boltsor rods 27 and 28 which extend axially through the upper and lowertransverse connecting bars 15 and 16 and through pivot openings in theforward ends of the links. The links are confined in place by the heads29 and nuts 30 of said bolts. The rear ends of said upper and lowerlinks are in a like manner pivoted to upper and lower bolts or rods 31,32 carried by the fork-spindle and located above and. below the steeringhead, respectively.

The lower pivot bolt 32 extends through and is supported by a two-partsleeve 33 which is carried by the lower end of the fork- As hereinshown, the fork-spindle is formed at its lower end with a .liorizontallywidened, forwardly extending rigid arm 34 to receive said twopartsleeve. The sleeve 33 is made in two transversely divided parts tofacilitate assembling it in the frame, as will be obvious from aninspection of Fig. 4. The upper pivot bolt 31 likewise extends throughand is supported by a sleeve 35 -which is made integral with arearwardly directed clam )ing collar which directly surrounds and isfixed rigidly to the fork-spindle at a point above the steering head.Said clamping collar is clamped on the spindle by a clamping bolt 37which extends transversely through apcrtured clamping lugs 38 at oneside of said collar. The said forkspindle is non-rotatively fixed insaid clamping collar, as will hereinafter more fully appear. The sleeves33 and 35 constitute spacing sleeves to maintain properly spaced therear ends of the links. Antifriction thrust bearings are interposedbetween said fork-spindle and steering head at the upp er and lower endsof the head, comprising upwardly and downwardly facing bearing rings and41 fitted to the upper and lower ends, respectively, of the tubularhead, opposing upper and lower bearing rings 42, 43 fitted to thespindle and balls 44 occupying ball races formed between opposingbearing rings. The said upper and lower bearing rings 40 and 41 areattached to the tubular head by integral, cylindric flanges 45, 46 whichfit tightly in the ends of said head. The lower spindle bearing memberor ring 43 is fitted stationary to an annular, upwardly facing shoulderon the spindle, while the upper spindle bearing member is interiorlyscrew threaded to engage exterior screw-threads of the upper end of thespindle. Said latter bearing ring or member constitutes means,therefore, by which both upper and lower bearings may be adjusted, itbeing observed that the spindle fits within the head without contacttherewith except at the upper and lower bearings.

The clamping collar 36, by which the upper spacing sleeve 35 issupported from the fork spindle, fits over the upper screwthreaded endof the fork-spindle above the upper spindle bearing ring 42, and saidcollar is confined between said bearing ring 42 and a nut 50 which hasscrew-threaded engagement with the spindle above said clamping collar.The clamping collar is provided on its inner cylindric wall with aplurality of angularly separated longitudinal ribs 51. which engagesimilarly arranged grooves 52 formed on the exterior surface of thescrewthreaded section of the fork-spindle. Said ribs and groovesconstitute an interlocking connection between the fork-spindle andcollar through which rotative movement of the spindle is transmitted tothe fork to turn the front or steering wheel. The clamping collar isplaced upon the screw-threaded end of the spindle after the upperantifriction bearing ring 42 has been adjusted and slips loosely downover the spindle. Thereafter, the collar is clamped up on the spindlethrough the action of the clamping bolt 37 so as to force the ribs ofthe collar closely into the grooves 51 of the spindle and thereby eifecta non-rotative interlocking connection between said parts. The saidnon-rotative clamping collar confined, as it is by the nut 50, againstthe screw-threaded bearing ring 42 serves as a means to lock saidbearing ring from rotation, and thus prevents derangement of the upperand lower spindle bearings, the adjustment of which is effected by saidnut 50.

The load carrying and shock absorbing spring device which yieldinglysupports the forward portion of the frame from the upper end of thefront fork, and which absorbs or cushions shocks and jars, due to thepassing of the machine over rough and uneven roadways, is connected atits upper end with the upper end of the fork and at its lower end withthe fork-spindle at a point below the steering head. All approved formof spring device is herein illustrated and is. made as follows: 55designates a spiral spring contained within a cylinder 56 which isconnected at its upper end with the upper trans verse connecting bar 15of the fork in a manner to swing in a vertical plane towards and fromthe steering head. Contained within and fitted closely to the wall ofsaid cylinder is a sliding piston 57 which is provided with a rod orstem 58 that extends downwardly through the coiled spring and an openingin the lower end wall or head 59 of said cylinder. Said piston rod isloosely connected at its lower end with the lower end of the forkstem.As herein shown, the lower end of said piston rod 58 enters a socketpiece 60 made integral with a sleeve 61 which surrounds a pin or bolt 62that extends transversely between and through lugs 63, 63 formedintegral with and extending forwardly from the fork-spindle arm 34. Theupper end of said cylinder 56 is connected with the upper transversefork bar 15 by means of a stirrup 68 which embraces said bar 15 and theside members of which are fitted to a prolongation of the upper head 69of said cylinder and secured thereto by a bolt 70. The upper end of saidprolongation of the head is formed with an upwardly opening concaverecess or seat to fit the cylindric surface of said bar 15, as clearlyshown in Fig. 2. Said bar 15 is provided with an annular recess 71 inwhich said stirrup and the recessed portion of the cylinder head fit,thus holding said parts from movement endwise of the bar. The spring 55is made of such length that the piston normally occupies a position nearthe upper end of the cylinder. Ashort spiral spring 72 is interposedbetween the upper end or head of the cylinder and the piston and servesas a yielding abutment against which the piston is formed by the recoilof the main cushioning spring 55, and also serves to hold the pistonfirmly against said main spring, thereby avoiding lost motion andpreventing rattling of the parts.

The piston fits closely within the cylinder, so as to'prevent the freeescape of air past the same when the piston moves downwardly in thecylinder. A close fit of the piston rod with the lower head of thecylinder is like wise provided. As a result of this construction thebody of air between the piston and lower cylinder head supplements thecushioning action of the spring 55. That is to say, the confined body ofair within the cylinder below the piston is compressed in the descent ofthe piston, so as to gradually retard its movement, and by its expansionit, to some degree, serves to aid the spring 55 in bringing the pistonback to its normal position. Any leakage of the air from the cylinderaround the piston or piston-rod will have substantially no effect withregard to its cushioning action, because such cushioning action will beneeded only in case of sudden and severe ars coming on the front forkand in such cases the movement of the piston in the cylinder will be soquick or rapid that the air will be compressed and will exert itsretarding action on the piston before it has time to escape inappreciable quantities. A very close or absolutely air-tight fit of thepiston and piston-rod in the cylinder is not, therefore, essential tothe production of the desired cushioning effect. Antifriction bearingsare provided between the links 25 and 26 and the ends of the connectingbars of the fork and spacing sleeves and carried by the spindle as follows: The said bars and spacing sleeves are enlarged at their outerends to form heads or flanges 7 4, 75. In the flat end faces of saidheads are formed circular annular grooves which oppose like annularderessions formed on the inner faces of the links; the said annulargrooves constituting annular ball races to receive antifriction balls78. The nuts of the cross-bolts or rods 27, 2 8, 31 and serves as meansfor confining the bearing balls in place and for adjusting the bearings.Said antifriction bearings serve to give great freedom of movementbetween the links and the parts to which they are ivoted.

T e construction described provides a hinged connection between theparallel forkspindle and the fork which maintains the parallel relationof said parts throughout their range of relative movement, therebypermitting ample relative movement of the parts under the control of thecushioning spring without imposing a bending or twisting stress on saidparts. The said links also constitute a lateral rigid connectionbetween. the fork and fork-spindle through which is transmitted thesteering movement of the spindle. The spring 55 yieldingly supports theload on the frame, the frame in rear of the fork being suspended fromthe lower end of the piston rod which is in turn supported on thecushioning spring 55 carried by the fork. The parallel links 25 and 26maintain the fork and its stem in such fixed relation that thecushioning action of the spring is impressed with uniform effect on theframe, thus securing a smooth and easy action of the spring.

The fork-spindle is made tubular to receive the stem 22 of the handlebar-sand said stem is locked in the tubular spindle by means of alock-nut 80 surrounding and having screw-threaded engagement with theupper end of the spindle and a split clamping ring 81 surrounding thehandle stem within said nut and provided with an exterior annular wedgesurface which is engaged by an interior annular wedge surface of thenut. The spindle is shown as made hollow throughout its length and thelower end of the opening therein is free or unobstructed. Thisarrangement permits circuit wires or other motor controlling devices tobe passed down through the spindle from the hollow handle bars andthence to the motor. This arrangement is advantageous because it placessuch motor controlling devices in the axis of rotation of the forkspindle, thus not only concealing said devices but also largely avoidingconstant bending thereof as the steering wheel is swung from side toside, such as would occur if the circuit wire or other motor controllingdevice be located at one side of the steering head.

I claim as my invention 1. In a bicycle frame, the combination with thefront fork comprising two forkmembers connected at their upper ends by across bar, a steering head in rear of the upper end of the fork, and afork-spindle rotatively mounted in the steering head, of links looselyconnected at their rear ends with the forkspindle at points above andbelow the steering head and loosely connected at their forward ends withthe fork, and a spring cushioning device connected at its u ppcr endwith the fork cross-bar and at its lower end with the fork-spindle at apoint below the steering head.

2. In a bicycle frame, the combination with the front fork comprisingtwo forkmembers connected at their upper ends by upper and lowerconnecting bars, a steering head in rear of the upper end of the fork,and a fork-spindle rotatively mounted in the steering head, of upper andlower pivot bolts carried by said spindle above and below the steeringhead, pivot bolts carried by said fork connecting bars, upper and lowerpairs of vertically swinging links pivoted to said fork and spindle, anda spring device carried by the upper connecting bar of the fork andpivotally connected at its lower end with the fork-spindle.

3. In a bicycle frame, the combination with the front fork comprisingtwo forkmembers connected at their upper ends by upper and lowerconnecting bars, a steering head in rear of the upper end of the fork,and a fork-spindle rotatively mounted in the steering head, of upper andlower pivot bolts carried by said spindle above and below the steeringhead, pivot bolts carried said fork connecting bars, upper and lowerpairs of vertically swinging links pivoted to said fork and spindle, andspacing sleeves carried by the spindle and surrounding said spindlepivot bolts.

4. In a bicycle frame, the combination with the front fork comprisingtwo forkmembers connected at their upper ends by upper and lowerconnecting bars, a steering head in rear of the upper end of the fork,and a fork-spindle rotatively mounted in the steering head, of upper andlower pivot bolts carried by said spindle above and below the steeringhead, pivot bolts carried by said fork connecting bars, upper and lowerpairs of vertically swinging links pivoted to said fork and spindle,spacing sleeves carried by the spindle and surrounding said spindlepivot bolts, and antifriction bearings between the lateral faces of thelinks and the spacing sleeves and fork connecting bars.

5. In a bicycle frame,. the combination with the front fork comprisingtwo forkmembers connected at their upper ends by upper and lower tubularconnecting bars, a steering head in rear of the upper end of the fork,and a fork-spindle rotatively mounted in the steering head, of upper andlower pivot bolts carried by said spindle above and below the steeringhead, pivot bolts extending through and supported in the tubularconnecting bars of the fork, upper and lower pairs of verticallyswinging links loosely connecting the pivot bolts of the fork andfork-spindle, spacing sleeves surrounding the spindle pivot bolts, theinner sides of said links and the ends of the spacing sleeves andconnecting bars being provided with registering annular grooves to formball-races, antifriction balls in said ball races and means afifordingyielding connection between the fork and spindle. 5

6. In a bicycle frame, the combinationl with the front fork comprisingtwo forkmembers connected at their upper ends by upper and lower tubularconnecting bars, a steering head in rear of the upper end of the fork,and a fork-spindle rotatively mounted in the steering head, of upper andlower pivot bolts carried by said spindle above and below the steeringhead, pivot bolts extending through and supported in the tubularconnecting bars of the fork, upper and lower pairs of verticallyswinging links loosely connecting the pivot bolts of the fork andfork-spindle, spacing sleeves surrounding the spindle pivot bolts, theinner sides of said links and the ends of the spacingv sleeves andconnecting bars being provided with registering annular grooves to formball-races, antifriction halls in saidball-races, nuts 011 the bolts forconfining the links and their antifriction bearings in place, and meansaffording yielding connection between the fork and spindle.

7. In a bicycle frame, the combination with the front fork thereof, asteering head mounted in rear of the upper end of the fork, and afork-spindle rotatively mounted in said steering head, said spindlebeing provided at its lower end with a forwardly directed arm, of atransversely arranged sleeve mounted in said arm, a second transversesleeve mounted on said spindle above the steering head, bolts extendingthrough and supported in said upper and lower sleeves, upper and lowerpairs of links pivoted at their rear ends to said bolts and at theirforward ends to parts carried by the upper end of the fork, and acushioning spring device affording yielding connection between the upperend of the fork and said rigid arm of the fork-spindle.

8. In a bicycle frame, the combination with the front fork thereof, asteering head mounted in rear of the upper end of the fork, and afork-spindle rotatively mounted in said steering head, said spindlebeing provided at its lower end with a forwardly directed arm, of atransversely arranged sleeve mounted in said arm, a second transversesleeve mounted on said spindle above the steering head, bolts extendingthrough and supported in said upper and lower sleeves, upper and lowerpairs of links pivoted at their rear ends to said bolts and at theirforward ends to parts carried by the upper end of the fork, said lowersleeve of the spindle being made of two parts and the arm of saidspindle being provided with a transverse opening into the opposite endsof which the parts of the sleeve are inserted and fixed, and acushioning spring device affording yielding connection between the upperend of the fork and said rigid arm of the fork-spindle.

9. In a bicycle frame, the combination with the front fork thereof, asteering head arranged in rear of the upper end of said fork, and afork-spindle rotatively mounted in the steering head, of upper and lowerpairs of links connecting the fork-spindle, at

points above and below the steering head, with the upper end of thefork, the connections between the rear ends of said links and thespindle comprising transversely arranged pivot bolts carried by thespindle, the upper one of which is contained within a sleeve whichextends between the upper pairs of links, and a collar integral withsaid upper sleeve which embraces the forkspindle above the steering headand is fixed thereon, and means affording yielding connection betweenthe upper end of the fork and said fork-spindle.

10. In a bicycle frame, the combination with the front fork thereof, asteering head arranged in rear of the upper end of said fork, and afork-spindle rotatively mounted in the steering head, of upper and lowerpairs of links connecting the fork-spindle, at points above and belowthe steering head with the upper end of the fork, the connectionsbetween the rear ends of said links and the spindle comprisingtransversely arranged pivot bolts carried by the spindle, the upper oneof which is contained within a sleeve which extends between the upperpairs of links, and a collar integral with said upper sleeve whichembraces the fork-spindle above the steering head and is fixed thereon,interfitting non-rotative connections between the collar and spindle,and means affording yielding connection between the upper end of thefork and said fork-spindle.

11. In a bicycle frame, the combination with the front fork thereof, asteering head arranged in rear of the upper end of said fork, and afork-spindle rotatively mounted in the steering head, of upper and lowerpairs of links connecting the fork-spindle, at points above and belowthe steering head with the upper end of the fork, the connectionsbetween the rear ends of said links and the spindle comprisingtransversely arranged pivot bolts carried by the spindle, the upper oneof which is contained within a sleeve which extends between the upperlinks, a collar integral with said upper sleeve which embraces thefork-spindle above the steering head, ball bearings between the upperand lower ends of the steering head and said fork-spindle, the bearingat the top of the head comprising an upper bearing member which hasscrew-threaded engagement with the spindle and arranged to adjust bothupper and lower bearings, said upper sleeve attaching collar engagingsaid upper bearing ring, a nut having screw-threaded engagement with thespindle above said collar and between which and said upper bearing ringthe collar is confined, and a spring affording a yielding connectionbetween the upper end of the fork and the lower end of the spindle.

12. In a bicycle frame, the combination with the front fork thereof, asteering head arranged in rear of the upper end of said fork, and afork-spindle rotatively mounted in the steering head, of upper and lowerpairs of links connecting the fork-spindle, at points above and belowthe steering head with the upper end of the fork, the connectionsbetween the rear ends of said links and the spindle comprisingtransversely arranged pivot bolts carried by the spindle, the upper oneof which is contained within a sleeve which extends between the upperlinks, a collar integral with said upper sleeve which embraces thefork-spindle above the steering head, antifriction bearings between theupper and lower ends of said steering head and spindle comprising upperand lower facing bearing rings fitted to the ends of the head, ballsinterposed between the lower bearing ring and a fixed annular bearingsurface on the spindle below the head, a bearing ring havingscrew-threaded engagement with the upper end of the spindle and opposingthe upper steering head bearing ring, balls interposed between saidupper bearing rings, said upper sleeve attaching collar being capable ofsliding endwise on the screw-threaded upper end of the spindle but heldnon-rotatively thereon, a nut having screw-threaded engagement with saidspindle above said collar and arranged to confine the collar between thesame and the upper screw-threaded ring of the upper antifrictionbearing, and a spring affording yielding connection between the upperend of the fork and said spindle.

13. In a bicycle frame, the combination with a steering head and afork-spindle rotatively mounted therein, and antifriction bearingsinterposed between the upper and lower ends of the head and saidspindle, the bearing at the top of the head embracing an upper bearingring which has screw-threaded engagement with the spindle above thesteering head and is arranged to adjust both the upper and lowerbearings, of upper and lower transversely arranged pivot bolts car riedby the spindle, one above and the other below the head, a sleevesurrounding the upper pivot bolt and provided with anintegral collarwhich encircles the screw-thread ed upper end of the spindle, a nuthaving screw-threaded engagement with said spindle above said sleeve andbetween which and the screwthreaded bearing ring of the upper bearingsaid sleeve is confined, said sleeve being movable endwise of thespindle but interlocked to prevent rotation thereon.

In testimony that I claim the foregoing as my invention I affix mysignature in the presence of two witnesses, this 21st day of December A.D. 1907.

AXEL LEVEDAIIL. Witnesses:

E. D. GRAY, O. I'IAMMERLUND.

